---
layout: docs
page_title: Connect to Dev Mode Target
description: |-
  Connecting to your first target
---

## Connect to Your First Target

The default target is a `tcp` target with a default port of `22` (which
corresponds to the default SSH port using TCP). This target is set up with
`127.0.0.1` as its address. When you execute `boundary connect` against this
target, a local authenticated proxy to the address is established on the
target's default port (`127.0.0.1:22`).

```shell-session
$ boundary connect -target-id ttcp_1234567890
```

There is also a secondary `tcp` target with (`ttcp_0987654321`) which uses host
sets instead of an address. The host sets for this target contain the default
host, which has the address 127.0.0.1. When you execute `boundary connect`
against this target, the single available host will be selected and a local
authenticated proxy to the host is also established on the target's default port
(127.0.0.1:22).

```shell-session
boundary connect -target-id ttcp_0987654321
```

For the purpose of this guide, both of these targets accomplish the same goal,
however they have different purposes. Refer to the
[domain](/boundary/docs/concepts/domain-model/index) documentation for more information.

For the rest of this guide, assume the default is used.

The output displays the address and port that your SSH client must utilize. In
the next section the `ssh` connect helper is used to make it easier to connect
to the target with a client.

The `boundary connect` command has a number of notable options, such as
`-listen-port` to choose the port on which the connect command will listen for
an incoming connection. This is convenient for allowing Boundary to work with
applications that allow you to select the connection address but not the port.
For many applications, there are still some extra hurdles that can exist, which
is why connect helpers can be useful.

The dev-mode default target allows you to make as many connections as you want
within the authorized session. When you are finished making connections, simply
`Ctrl-C/Command-C` the `boundary connect` process to shut down the session.

### Using Connect Helpers

Boundary includes connect helpers that automatically accept host SSH key prompts
for you. These are written as `boundary connect <subcommand>`. 

In the following example, the helper will automatically execute `ssh` for you,
filling in the local address and port. An expected host ID is set to avoid
warnings on future connections when a different port is allocated automatically.
A host key must still be accepted upon first connect.

```shell-session
$ boundary connect ssh -target-id ttcp_1234567890
```

If you want to pass additional flags to the SSH client, add them to the command
line separated by a double-dash; anything after the double dash will be passed
to the executed client. For instance:

```shell-session
$ boundary connect ssh -target-id ttcp_1234567890 -- -l some-other-user
```

There is also a `-style` flag to allow the command to format arguments in a
different style expected by different SSH clients. Besides the default `ssh`,
the `boundary connect ssh` command supports `-style putty` to support passing
connection information to PuTTY.

One advantage to styles is that Boundary will provide information to the client
in the format that makes sense. For example, the `-username` flag is used to
specify a username other than your currently logged-in user. This ensures that
regardless of your `-style` choice, the username is properly passed to the
executed client, and you don't need to figure out the syntax yourself.

## Selecting Targets

When using `boundary connect` you must identify the target used for connecting.
Convention in this documentation is to use the target ID because it refers to a
single explicit value, however other flags are supported:

- `target-name`: The name of the target
- `target-scope-id`: The ID of the scope in which the target lives
- `target-scope-name`: The name of the scope in which the target lives

Note however that these are not uniquely identifying, as names can be re-used
across scopes. As a result, when not using the target ID, you must use the
target's name in conjunction with the scope name or scope ID so that Boundary
can correctly identify the desired target.

Here is an SSH example in dev mode:

```shell-session
$ boundary connect ssh -target-name "Generated target" -target-scope-name "Generated project scope"
```

## Built-In vs. Exec

Boundary comes with built-in wrappers for popular layer 7 connection protocols,
such as:

- `ssh`: defaults to the local SSH client (`ssh`)
- `postgres`: defaults to the official Postgres CLI client (`psql`)
- `rdp`: defaults to the built-in Windows RDP client (`mstsc`)
- `http`: defaults to `curl`
- `kube`: defaults to `kubectl`

However, `boundary connect` can accommodate executing clients even when there is
no built-in support for a specific client using `-exec`. The `-exec` flag is a
very powerful tool, allowing you to wrap Boundary TCP sessions in your preferred
client. You can use this flag to create an authenticated proxy to almost
anything.

Whether using `-exec` or one of the listed helpers, you can pass flags to the
executed command by including them after a double-dash `--`:

```shell-session
$ boundary connect ssh -target-id ttcp_1234567890 -- -l myuser -i ~/.ssh/identity
```

You also have access to some templated values that are substituted into the
command arguments, and these values are additionally injected as environment
variables in the executed command:

- `{{boundary.ip}}` (`BOUNDARY_PROXIED_IP`): The IP address of the listening
  socket that `boundary connect` has opened.
- `{{boundary.port}}` (`BOUNDARY_PROXIED_PORT`): The port of the listening
  socket that `boundary connect` has opened.
- `{{boundary.addr}}` (`BOUNDARY_PROXIED_ADDR`): The host:port format of the
  address. This is essentially equivalent to `{{boundary.ip}}:{{boundary.port}}`.

For example, if you wanted to use Boundary to create an authenticated firewall
around 'curl', you could update the default TCP target from a default port
of `:22` to `:443`:

```shell-session
$ boundary targets update tcp -default-port 443 -id ttcp_1234567890

Target information:
  Address:                    127.0.0.1
  Created Time:               Fri, 25 Sep 2020 18:35:47 PDT
  Description:                Provides an initial target in Boundary
  ID:                         ttcp_1234567890
  Name:                       Generated target
  Session Connection Limit:   1
  Session Max Seconds:        28800
  Type:                       tcp
  Updated Time:               Fri, 25 Sep 2020 18:36:18 PDT
  Version:                    2

  Scope:
    ID:                       p_1234567890
    Name:                     Generated project scope
    Parent Scope ID:          o_1234567890
    Type:                     project

  Attributes:
    Default Port:             443
```

In the output above the default port for the target has now changed to `:443`.

Now, `curl` can be used as the executed client for the TCP target session to do
an authenticated download of hashicorp.com:

```shell-session
$ boundary connect -exec curl -target-id ttcp_1234567890 \
         -- -vvsL --output /dev/null hashicorp.com

*   Trying 76.76.21.21...
* TCP_NODELAY set
* Connected to hashicorp.com (76.76.21.21) port 80 (#0)
> GET / HTTP/1.1
> Host: hashicorp.com
> User-Agent: curl/7.64.1
> Accept: */*
...<truncated output>...
```

Note that `-exec` is available for subcommands that wrap clients as well. As an
example, if `putty.exe` is available on a Windows host but the command is being
run from WSL, the following allows usage of the wrapper while specifying the
correct available binary (as WSL must use `.exe` when invoking Windows binaries):

```shell-session
$ boundary connect ssh -style putty -exec putty.exe -target-id ttcp_1234567890
```

## Connect using Desktop Client

While using the desktop client, choose the target and connect to retrieve local
proxy details.

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## Next Steps

See our [basic administration
workflows](/boundary/tutorials/oss-administration)
for in depth discussion on managing scopes, targets, identities, and sessions.